Crystal

In a recent survey we carried out about car servicing, over 55% of people chose their filters based on price alone. Now we're not going to tell you that more expensive filters are better, because it isn't true. What we will tell you is that not all filters are the same.

Take a look at this study by MANN-FILTER of comparable oil filters, all claiming to be made to 'OE' Original Equipment specification, the results are quite shocking.

Click on the 'Fullscreen' button to enlarge

From the outside, different brands of spin-on oil filters all look virtually identical so how do you pick a good brand? Well, one way would be to choose a brand that is willing to put their products under the microscope like MANN have above. The other route we'd go down would be to pick a brand that is fitted by the vehicle manufacturer at the factory as Original Equipment (remember car manufacturers as a rule don't make their own filters) As an example, if you buy a 'genuine' BMW filter, it may come in a BMW box and have the BMW logo on the parts, but the filter itself will actually be manufactured by a 3rd party supplier, in BMW's case, either Mahle, Knecht & Mann.

Roof Bars can be fitted to virtually any car or van, they're a great way of increasing your load carrying capacity and improving the versatility of your vehicle. They're popular in both work and leisure applications and are commonly used for carrying oversize items such as ladders, timber, piping, roof boxes, surf boards and bike racks but can be used to transport virtually anything.

Before you start shopping for Roof bars, there's a couple of things you need to know, our quick guide below will help identify what type of Roof Bars are suitable for your vehicle

There's considerable hype surrounding the re-invigorated championship this year. The regulations have been opened up, tyre choices broadened, new sponsors attracted and in general a huge amount of work has been done to attract competitors and fans alike back to the series....and it's worked, at the time of writing, over 20 drivers have signed up and record numbers were out pre-season testing.

The first thing you should know about spark plugs is that they are only used in petrol engines. Diesel engines use a different component called a glow plug.

This is what a typical spark plug looks like

The purpose of a spark plug is to repeatedly create a strong electrical spark. To understand why your engine needs a spark, you need to know a little bit about how an engine works.

There are 4 main steps that take place inside your engine to make it run:

Step 1) A mixture of petrol and air is sucked into the combustion chamber by the piston moving down inside the cylinder.

Step 2) The petrol & air mixture is squeezed in the combustion chamber by the piston moving up inside the cylinder.

Step 3) The petrol & air mixture is ignited by the spark plug. this causes an explosion inside the combustion chamber. The force of the explosion pushes the piston back down inside the cylinder.

Step 4) The spent gasses that result from the explosion are then forced out of the combustion chamber by the piston.

While the engine is running this whole process is repeatedly taking place thousands of times a minute. Interestingly, the sound that your engine makes is actually the sound of thousands of those little explosions taking place inside your cylinders. The animation below of a standard 4 cylinder engine is slowed down so that you can see the process

The video below probably makes it easier to understand. It shows what actually happens inside a real working engine. It's slowed down dramatically so you can see what's going on. First you can see the petrol & air mixture rushing in to the combustion chamber, through the inlet valve. The piston then comes into shot, compressing the mixture, the spark plug fires and ignites the fuel mixture, the force of the explosion pushes the piston back down, the exhaust valve opens and the piston pushes the old gasses out.

The spark plug converts electrical energy into a spark. The electrical energy comes from the battery, which is then amplified by ignition coils, it's then routed to the individual spark plugs via ignition leads. The spark plug itself creates the spark by forcing the electrical energy to jump the gap between the central electrode and the earth electrode

When should you change your spark plugs?Spark plugs wear out and need to be changed. The recommended change intervals vary from car to car but as a rule of thumb it should be every 15,000-20,000 kms. Worn plugs will result in reduced fuel economy and reduced engine power.

Which spark plugs do I need?
The easiest way to select the correct spark plugs for your car is by using our reg lookup system. Our system will show you multiple brands of plug, all of which will be suitable for your car, you just need to check the descriptions carefully in-case of limitations and then choose your preferred brand or price point.

How do I fit new spark plugs?
Fitting new spark plugs is one of the easier DIY jobs you can do with very little equipment or experience. The key points to remember are:

Take extra car not to cross thread the new plugs when fitting them, they should go in with very little resistance

Don't over tighten the plugs - Check the correct torque settings & use a torque wrench where possible

Make sure you re-fit the HT/ignition leads in the same position (it may help to number them)

This week I've done something very sensible....I've just bought a new car. It's a diesel...............and I think I hate it.
The car in question is a Peugeot 307 1.4 HDI. It's the motoring equivalent of a vasectomy. It's an appliance, a dull, cheap plastic, poverty spec, lifeless transport module designed to be frightfully frugal whilst delivering you and your children from point A to point B. Apparently it's turbocharged, but I'm yet to feel any evidence to back that up in its performance and I'm so disinterested in it that I can't be bothered to look under the bonnet to see if there's a turbo in there. It has wind up windows, manually adjusting mirrors and a whole lot of buttons on the dashboard that are blanked off and do nothing...and it kind of smells funky.
Here it is. I do quite like the colour.

Your probably wondering why I'm complaining so comprehensively about a car I've just bought. Well actually, I didn't buy it, I swapped it, with my old car because I needed something sensible and cheap for a while. My old car, despite also being a Peugeot, and being a bit rubbish, was at least interesting. It was a 206 Gti, which is the 2 litre, 180bhp version of the popular little French hatchback.
Here it is. I quite liked it:

It had many, many things wrong with it and in my 6 short months of ownership it cost me quite a lot of money. It had questionable wheel arch extensions, it was lowered and had appalling ride quality, but it had some very sexy Team Dynamics alloys, beautiful Recaro style Alcantara bucket seats, a close ratio gearbox and when it hit 5000rpm it went like shit off a stick and sounded incredible. Every time you got into it, it was an occasion, and that's what I like in a car. It doesn't have to be fast, expensive or flashy, it just has to be interesting. It has to have character. The 206 had it, the 307 doesn't.

What the 307 does do is take tiny, tiny, mouse-sized sips of diesel. I've only owned it for 48 hours and done about 100 miles in it but the fuel gauge genuinely hasn't moved a millimeter. Other redeeming features are relatively thin on the ground....it does have interesting wipers, they go from the middle of the screen outwards. It has nice soft suspension and and I can now drive over speed bumps like a normal person, instead of having to crab across them at an angle. The biggest positive point is that it doesn't actually have anything wrong with it, it feels quite strange, I've nothing to tinker with. I guess i'll tackle that funky smell!